Health blog page

October 10, 2007, 5:21 PM CT

Folic acid lowers blood arsenic levels

A new study conducted in Bangladesh finds that folic acid supplements can dramatically lower blood arsenic levels in individuals chronically exposed to arsenic-contaminated drinking water. Arsenic is a toxic element that is naturally present in some soils and water. Arsenic-contaminated drinking water is currently a significant public health problem in at least 70 countries, including several developing countries and also parts of the United States. Chronic arsenic exposure is linked to increased risk for skin, liver and bladder cancers, skin lesions, cardiovascular disease, and other adverse health outcomes. The study was funded by the National Institute of Environmental Health Sciences (NIEHS) at the National Institutes of Health (NIH).

Scientists observed that therapy with 400 micrograms a day of folic acid, the U.S. Recommended Dietary Allowance, reduced total blood arsenic levels in a Bangladesh study population by 14 percent. Folate is a B vitamin found in leafy vegetables, citrus fruits, beans, and whole grains. Folic acid can also be taken as a vitamin supplement, and in the United States, it is added to flour and other fortified foods. The scientists observed that folate deficiency is very common in Bangladesh, where the study was conducted, but is not as problematic in the United States due to folate fortification. Additional studies are needed to determine if folic acid similarly lowers blood arsenic in populations where folate deficiency is less common, such as in the United States......... Posted by: Julia      Read more         Source

June 12, 2007, 5:10 AM CT

Sleep problems may affect a person's diet

Sleep problems can influence a persons diet. Those who dont get enough sleep are less likely to cook their own meals and, instead, opt to eat fast food. It is the lack of nutritional value of this restaurant-prepared food that may cause health problems for these people in the long-run, as per a research abstract that will be presented Monday at SLEEP 2007, the 21st Annual Meeting of the Associated Professional Sleep Societies (APSS).

Mindy Engle-Friedman, PhD, of the City University of New York, surveyed nine females and 12 males, all undergraduates who completed a "sleep and eating habits" questionnaire. For seven days, the participants completed diaries, with each entry detailing how much sleep they got the night before and what they ate the following day.

Preliminary findings showed that individuals reporting problems with total sleep time, sleep latency and awakenings were more likely to eat restaurant-prepared or fast food rather than food made at home on day two than were individuals with no reported sleep problems. Further, individuals with sleep problems were also less likely to eat food prepared at home on days four and seven.

"Persons with sleep complaints are less likely to eat at home. These meals may require less effort and may be less healthful than meals prepared at home. Over time, persons with sleep complaints may have weight or health problems correlation to their nutrition," said Engle-Friedman......... Posted by: Julia      Read more         Source

June 10, 2007, 9:27 PM CT

"Nurse Cells" Make Life and Death Decisions

"Nurse cells" play an important role in deciding which developing infection-fighting cells, called T cells, live and which die, according to research funded by the National Science Foundation (NSF) and reported in the recent issue of the journal Experimental Biology and Medicine.

The infection-fighting cells, known as thymocytes or T cells, live in the thymus, an organ in the upper portion of the chest. Loss of the thymus results in severe immunodeficiency and increased susceptibility to infection. The function of T cells produced by the thymus is to recognize harmful invaders. Once invaders have been identified, T cells then attempt to eliminate disease-infected cells.

"In early studies, it was suggested that thymic nurse cells only removed non-functional thymocytes," said Eve Barak, program director in NSF's Division of Molecular and Cellular Biology. "This research shows that nurse cells are performing a much bigger role in the thymus than we thought".

Thymic nurse cells were given their name because of their close relationship with thymocytes. These nurse cells have been reported to take up as many as 50 destined-to-die thymocytes into their own cell bodies.

Thymic nurse cells were discovered in 1980. Their existence was debated because many scientists found it difficult to believe that a cell could internalize another cell, said Jerry Guyden, a biologist at the City College of New York and lead researcher......... Posted by: Julia      Read more         Source

April 24, 2007, 10:27 PM CT

High insulin levels impair intestinal metabolic function

Nutritional scientists at the University of Alberta are the first to establish a connection between high insulin levels and dysfunction of intestinal lipid metabolism in an animal model. They believe this finding supports their contention that impaired intestinal metabolic function plays a critical role in the development of cardiovascular disease.

The research was published recently in the journal Atherosclerosis.

The researchers have found that excessive insulin appears to slow the removal of chylomicrons from the blood stream following a fatty meal. Chylomicrons transport dietary fat from the intestine to the rest of the body.

The researchers note that excessive insulin appears to alter the mechanics of blood vessel walls, allowing chylomicrons and cholesterol to build up in them, which, over time, creates blockages in the blood stream, leading to heart problems.

"Now that we know high levels of insulin are associated with altered intestinal chylomicron metabolism and a build up of these particles in the blood vessel walls, our next step is to use this animal model to look closer at the cellular mechanisms and try to figure out how this happens," said Dr. Donna Vine, a nutritional scientist at the U of A and co-author of the paper in Atherosclerosis......... Posted by: Julia      Read more         Source

April 10, 2007, 6:35 PM CT

Misusing vitamin to foil drug test

Taking excessive doses of a common vitamin in an attempt to defeat drug screening tests may send the user to the hospitalor worse.

Researchers from The Children's Hospital of Philadelphia and The University of Pennsylvania reported on two adults and two adolescents who suffered toxic side effects from taking large amounts of niacin, also known as vitamin B3, in mistaken attempts to foil urine drug tests.

Both adult patients suffered skin irritation, while both adolescents had potentially life-threatening reactions, including liver toxicity and hypoglycemia (low blood sugar), as well as nausea, vomiting and dizziness. One of the teens also had disrupted heart rhythms.

All four patients recovered after treatment in hospital emergency rooms for the adverse effects. The report appeared online in the Annals of Emergency Medicine.

"Testing urine for drugs is becoming increasingly common for job applicants," said study leader Manoj K. Mittal, M.D., a fellow in Emergency Medicine at The Children's Hospital of Philadelphia. "Because niacin is known to affect metabolic processes, there is a completely unfounded claim that it can rapidly clear the body of drugs such as cannabis and cocaine. However, niacin is toxic when taken in large amounts".

Niacin is easily available as an over-the-counter vitamin supplement. As a vitamin, the daily recommended intake is 15 milligrams, but niacin is used in much larger doses to treat vitamin deficiencies and other conditions. "People often assume niacin is completely safe," said Dr. Mittal. "As a water-soluble vitamin, it is easily excreted from the body. However, the body has its limits, and some of these patients took 300 times the daily recommended dose of niacin." Dr. Mittal added that there is a report in the medical literature of a patient who suffered liver failure, requiring a liver transplant, after taking excessive doses of niacin......... Posted by: Julia      Read more         Source

April 2, 2007, 10:18 PM CT

Flexible Electronics As Sensors

Flexible electronic structures with the potential to bend, expand and manipulate electronic devices are being developed by researchers at the U.S. Department of Energy's Argonne National Laboratory and the University of Illinois at Urbana-Champaign. These flexible structures could find useful applications as sensors and as electronic devices that can be integrated into artificial muscles or biological tissues.

In addition to a biomedical impact, flexible electronics are important for energy technology as flexible and accurate sensors for hydrogen.

These structures were developed from a concept created by Argonne scientist Yugang Sun and a team of researchers at the University of Illinois led by John A. Rogers. The concept focuses on forming single-crystalline semiconductor nanoribbons in stretchable geometrical configurations with emphasis on the materials and surface chemistries used in their fabrication and the mechanics of their response to applied strains.

"Flexible electronics are typically characterized by conducting plastic-based liquids that can be printed onto thin, bendable surfaces," Sun said. "The objective of our work was to generate a concept along with subsequent technology that would allow for electronic wires and circuits to stretch like rubber bands and accordions leading to sensor-embedded covers for aircraft and robots, and even prosthetic skin for humans......... Posted by: Julia      Read more         Source

April 1, 2007, 9:33 PM CT

The formation of social memories

Is there a specific memory for events involving people? Researchers in the Vulnerability, Adaptation and Psychopathology Laboratory (CNRS/University Paris VI France ) and a Canadian team at Douglas Hospital, McGill University (Montreal), have identified the internal part of the prefrontal cortex as being the key structure for memorising social information. Published in Journal of Cognitive Neuroscience, February 2007.

Social events such as a party with friends, a work meeting or an argument with a partner form an integral part of daily life. Our ability to remember these events, and more precisely to remember the people and the relationships we had with them, is essential to ensure satisfactory adaptation to our social existence. At a cerebral level, various regions of the brain, and particularly the hippocampus, are directly involved in learning and memory. Some of these regions are specialised in learning certain types of information, such as the amygdale and our memory for emotions.

The Canadian and French teams (the latter led by Philippe Fossati ) have recently identified a precise region in the frontal cortex which may be specialised in recording and learning social information. Using a functional magnetic resonance imaging technique, the scientists measured cerebral activity in 17 volunteers while they accomplished a memory task involving pictures of social scenes (interacting individuals) and non-social scenes (landscapes with no people). They thus identified the internal part of the prefrontal cortex, called the medial prefrontal cortex, as being the key structure in memorising social information from a picture......... Posted by: Julia      Read more         Source

March 25, 2007, 9:06 PM CT

Low-dose aspirin Vs high-dose aspirin

The use of medicines to fight cardiovascular disease has been a primary focus of research in this area for the past several decades, as combinations of interventions and medicinal treatment have gradually begun to increase long-term survival rates. Two studies presented today at the American College of Cardiology's 56th Annual Scientific Session look at the measurable impact of the use of aspirin and other maintenance therapies, and one demonstrates that lower doses of therapies may prove to be just as beneficial while also lowering side effects. ACC.07 is the premier cardiovascular medical meeting, bringing together heart specialists and cardiovascular specialists to further breakthroughs in cardiovascular medicine.

"Cardiovascular disease is the leading cause of death today, and the major focus of research is to find better ways to help these patients through prevention, immediate intervention and long-term therapy regimens," said Douglas P. Zipes, M.D., Distinguished Professor of the Indiana University School of Medicine. "As we continue to discover the benefits of these therapies, we expect to see continued and measurable improvements in overall survival and quality of life".

Effects of Aspirin dose on Ischemic Events and Bleeding after Percutaneous Coronary Intervention (PCI): Insights from the PCI-CURE Study (Presentation Number: 2805-9)......... Posted by: Julia      Read more         Source

March 6, 2007, 3:32 PM CT

Receptor For Alcohol Pleasure And Problems

A genetic variant of a receptor in the brains reward circuitry heightens the stimulating effects of early exposures to alcohol and increases alcohol consumption, according to a new study by researchers at the National Institute on Alcohol Abuse and Alcoholism (NIAAA), part of the National Institutes of Health (NIH). Conducted in rhesus monkeys, the study extends previous research that suggests an important role for a similar brain receptor variant in the development of human alcohol use disorders. A report of the findings is published in the March, 2007 issue of the Archives of General Psychiatry.

"Although the pathway to alcoholism is influenced by many factors, our findings affirm that individuals who possess this receptor variant may experience enhanced pleasurable effects from alcohol that could increase their risk for developing alcohol abuse and dependence," notes Markus Heilig, M.D., Ph.D., NIAAA Clinical Director and the studys senior author.

Molecules known as opioid peptides bind to opioid receptors in the brain to signal experiences of reward and reinforcement, as well as the euphoria and other positive subjective effects produced by alcohol. Previous studies have shown that, among the brains various subtypes of opioid receptors, the mu-subtype is most likely responsible for transmitting alcohols positive effects......... Posted by: Julia      Read more         Source

March 5, 2007, 9:58 PM CT

Protein That Appears To Regulate Bone Mass Loss

Typically typically an estimated ten million americans suffer from osteoporosis, and another 34 million americans are at risk of developing the disease, which is characterized by a severe loss of bone mineral density, fragile bones and an increased risk of hip, spine and wrist fractures. The basic mechanism behind osteoporosis involves an imbalance between bone mineral formation and loss, but the detailed biological processes that lead to this imbalance are not completely understood. Now researchers at the National Institute of Allergy and Infectious Diseases (NIAID), one of the National Institutes of Health (NIH), and colleagues are reporting new insights into the biology of bone loss based on a study of 14 people with a rare genetic disorder called X-linked Hyper IgM Syndrome.

X-linked Hyper IgM Syndrome strikes about one in a million American--all males--and is caused by a deficiency in an important immune system protein known as CD40 ligand. This protein is crucial for the development and maturation of immune cells, and without it people with X-linked Hyper IgM Syndrome are susceptible to a range of opportunistic infections. Last year, an NIAID doctor treating children with this disease observed that several of them sustained unexplained rib fractures that he hypothesized could be, like osteoporosis, caused by a loss of bone mineral density. A new study, published online this week, confirms this unexpected connection. CD40 ligand appears to regulate cells that secrete chemicals that block bone metabolism, and the loss of this protein in people with X-linked Hyper IgM Syndrome appears to accelerate bone loss. The next step, say the researchers, is to determine whether experimental treatments designed to correct the immune deficiency of X-linked Hyper IgM Syndrome can also reverse the bone loss. If so, the knowledge gained from these studies may benefit people at risk of developing osteoporosis......... Posted by: Julia      Read more         Source

February 26, 2007, 7:53 PM CT

The metabolic response to colitis

A new study being published by the American Physiological Society (www.The-APS.org) finds that the body responds differently to colitis (inflammation of the colon) based on whether the disease is acute (sharp and brief) or chronic (long-term). Researchers, using an experimental mouse model of colitis, discovered that the effects of acute colitis were associated with decreased body weight, food intake, and body fat content. Chronic colitis was associated with reduced body fat content, decreased bone mineral density and attenuated use of energy, termed energy expenditure. The discovery may help lead to better symptom management for the 500,000 Americans who live with the disease.

The study, "Mice With Experimental Colitis Show an Altered Metabolism With Decreased Metabolic Rate, " was conducted by Silvia Melgar and Erik Michalsson, Integrative Pharmacology, GI Biology, AstraZeneca; Lennart Svensson, Department of Molecular Pharmacology, AstraZeneca; Anna-Karin Gerdin and Mohammad Bohlooly-Y, AstraZeneca Transgenics and Comparative Genomics Centre, AstraZeneca, Molndal, Sweden; and Mikael Bjursell, Department of Physiology/Endocrinology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, Goteborg University, Sweden and AstraZeneca Transgenics and Comparative Genomics Centre, AstraZeneca, Molndal, Sweden. Their study appears in the Articles in Press Section of the American Journal of Physiology, Gastrointestinal and Liver Physiology. The journal is one of 11 peer reviewed scientific publications issued each month by the American Physiological Society (APS)......... Posted by: Julia      Read more         Source

February 26, 2007, 6:39 PM CT

Usefulness of cardiovascular disease test?

Scientists with Dartmouth Medical School and the Veterans Affairs Outcomes Group at the White River Junction (Vt.) VA Medical Center are questioning the usefulness of the C-Reactive Protein (CRP) test for guiding decisions about the use of cholesterol-lowering medication.

The scientists show that adding CRP testing to routine assessments would increase the number of Americans eligible for cholesterol-lowering therapy by about 2 million if used judiciously, and by over 25 million if used broadly-with most of these people being at low risk for heart attacks or heart disease. The authors argue that the medical community should focus energies on treating high-risk patients before expanding the pool to include so a number of low-risk patients. Their study was reported in the recent issue of the Journal of General Internal Medicine.

"There is a push to use this test, and that probably doesn't make much sense," says Steven Woloshin, one of the authors on the paper and an associate professor of community and family medicine at Dartmouth Medical School (DMS).

As per co-author Lisa Schwartz, associate professor of medicine at DMS, "A general population use of the test would identify millions of low-risk people, and we don't know if exposing them to cholesterol medications will do more good than harm. Plus, focusing on low-risk people seems misplaced since over half of high-risk people, who we know are helped by therapy, remain untreated"......... Posted by: Julia      Read more         Source

February 26, 2007, 6:34 PM CT

Barnyard Emissions And Asthma

Reducing barnyard emissions is one way to help reduce the harmful effects of tiny atmospheric air particles that can cause severe asthma in children, and lung cancer and heart attacks in some adults.

Carnegie Mellon University researcher Peter J. Adams argues that improved control of ammonia emissions from farm barnyards is more economical and efficient than trying to control the effects of sulfur dioxide and nitrogen oxide pollution from some industrial plants.

"In most farms, handling of animal manure is a major source of ammonia being released both to air and water," said Adams, an associate professor of civil and environmental engineering at Carnegie Mellon. "Our research shows that increased control of livestock feed, efficient use of nitrogen on farms, low-emission fertilizers and other improvements to manure handling on farms are cost-effective ways to reduce ammonia emissions and airborne particles".

Adams research, featured in the 2007 winter edition of Environmental Science & Technology, shows that ammonia is a significant contributor to dangerous airborne particle concentrations along the eastern United States concentrations that the Environmental Protection Agency (EPA) deems hazardous to human health.

The Carnegie Mellon research also reports that the potential savings from controlling ammonia manure emissions from farms is $8,000 per ton in the winter, a cheaper and overlooked strategy for reducing airborne particle levels compared to controlling dangerous industrial pollutants like sulfur dioxide and nitrogen oxides. In New York state, each 500-megawatt, gas-burning turbine produces as much as 61 tons per year of pollutants, such as sulfur dioxide and other dangerous airborne particulates, with remediation costs well into the millions, researchers said......... Posted by: Julia      Read more         Source

February 20, 2007, 7:54 PM CT

Mental And Physical Health Of Caregivers

Having positive cultural beliefs about caring for elders and strong religious beliefs can ward off depression and other mental health difficulties for female caregivers of spouses and parents with dementia, but sustained elevated levels of the stress hormone, cortisol, puts these women at risk for physical health problems, according to a study published in the American Journal of Geriatric Psychology.

"Caregiving for someone with dementia is stressful for almost everyone and can negatively influence mental and physical health," said T. J. McCallum, assistant professor of psychology at Case Western Reserve University.

Since stress is common in caregiving, McCallum, along with Kristen H. Sorocco from the University of Oklahoma's Health Sciences Center, and Thomas Fritsch, formerly of Case's University Memory and Aging Center (who is now at the University of Wisconsin at Milwaukee), set out to study how different cultural and religious beliefs in different ethnic groups impact the overall health of the caregivers.

In a pilot study, the researchers studied 54 caregivers (30 African Americans and 24 European Americans) and compared their mental health and cortisol levels with 64 non caregivers (48 African Americans and 15 European Americans). The participants were closely matched for their income levels, college education and length of time caring for their family members (less than five years). Each caregiving group spent a similar amount of time bathing, dressing, preparing food and other activities to care for their loved ones......... Posted by: Julia      Read more         Source

February 13, 2007, 8:49 PM CT

Genetic Testing Of Degenerative Eye Disease

ANN ARBOR, Mich. Genetic testing for eye disease is providing vital information about complex retinal diseases, especially when used to confirm a clinicians diagnosis.

In a newly published review of such tests that were conducted over a five-year period at the University of Michigan Kellogg Eye Center, scientists were able to confirm a clinicians diagnosis in half of the cases. The testing took place in the laboratory of Radha Ayyagari, Ph.D., director of Kelloggs Ophthalmic Molecular Diagnostic Laboratory.

In the recent issue of Archives of Ophthalmology, Ayyagari and her colleagues report on 350 genetic tests conducted since 1999, when the U-M Ophthalmic Molecular Diagnostic Laboratory became one of the first laboratories in the nation to receive government approval for ophthalmic testing under the Clinical Laboratory Improvement Amendment (CLIA). For each test described in the current study, scientists analyzed one or more of eight genes known to cause diseases of the retina.

Of the 350 tests, 266 were performed to confirm a clinicians diagnosis, by far the most common use of genetic testing for eye disease. Another 75 tests sought to determine whether an individual was a carrier of a disease, and nine tests were used to predict the likelihood that an individual with a family history of a given eye disease would go on to develop it......... Posted by: Julia      Read more         Source

February 12, 2007, 8:57 PM CT

For Individuals With Genetic Disorders

A new study published in the February 2007 issue of the American Journal of Medical Genetics reveals that individuals with genetic conditions are twice as likely to report having been denied health insurance than individuals with other chronic illnesses. The Johns Hopkins University study also found that nearly 60 percent of all study participants believe a health insurance company can obtain medical information about them without their permission. Researchers conducted in-depth, personal interviews of 597 adults for the project, believed to be the first large-scale study to systematically compare and contrast the health insurance experiences, attitudes, and beliefs of persons with genetic conditions versus individuals with other serious medical conditions. Respondents (or their children) had sickle cell disease, cystic fibrosis, breast cancer, colon cancer, diabetes, or HIV.

"Anyone with chronic medical conditions should be legitimately concerned about access to health insurance, but individuals with genetic conditions may have additional reasons to worry," said principal investigator Nancy Kass, ScD, deputy director for public health at the Johns Hopkins Berman Institute of Bioethics and a professor at the Johns Hopkins Bloomberg School of Public Health. "We learned that there is considerable concern about being denied health insurance because of a genetic condition, as well as maintaining some privacy about the status of that condition"......... Posted by: Julia      Read more         Source

February 7, 2007, 5:08 AM CT

Children's sleep problems

It is obvious that young children who have difficulties sleeping are likely to have problems in school. A new study shows that African-American children and children from lower socioeconomic backgrounds fare worse than their counterparts when their sleep is disrupted.

The study offers one of the first demonstrations that the relationship between children's performance and sleep may differ among children of different backgrounds. Conducted by researchers at Auburn University and Notre Dame University, it is published in the January/February 2007 issue of the journal Child Development.

The study looked at 166 8- and 9-year-old African-American and European-American children from varying socioeconomic backgrounds. The children's sleep habits were measured through wristwatch-sized activity monitors they wore during sleep for one week, sleep diaries of bedtimes and wake-up times, and reports of sleep quality and sleep-related problems such as sleepiness during the day. The children also were given individual cognitive tests measuring a range of mental functions related to school achievement.

When children's socioeconomic status was taken into consideration, African-American and European-American children's performance on cognitive tests was similar when they slept well, the study found. But when sleep was disrupted, African-American children's performance was worse. Similarly, children from lower and higher socioeconomic backgrounds performed similarly on tests when they slept well and their sleep schedules were consistent. But when their sleep was disrupted, children from higher-income homes did better than children from lower-income homes. The study did not address why African-American children and youngsters from lower-income homes may be more vulnerable to the effects of sleep disruption.........

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January 24, 2007, 7:57 PM CT

Discovery Of Diabetes Fighting Molecule

University of California, Riverside Assistant Professor of Bioengineering, Jiayu Liao played a pivotal role in the discovery of a small molecule that has been shown to control diabetes in mice and may pave the way to the development of easier treatment for adult-onset diabetes.

This discovery was a collaboration between Liao at UC Riverside's Bourns College of Engineering and a team in the National Center for Drug Screening, Shanghai, which is part of the Chinese Academy of Science.

This key molecule, identified as Boc5, can stimulate insulin function in response to high levels of glucose as well as reduce body weight by 20 percent. The discovery of this molecule that stimulates the production of the intestinal hormone glucagon-like peptide1 (GLP1), which metabolizes glucose, has been an extremely difficult goal for researchers in both academics and the pharmaceutical industry.

Boc5 is the first small molecule activator for Class B GPCRs, which regulate hormones in many human physiological processes and are major targets for pharmaceutical companies. This discovery opened new revenue possibilities to support future research into small molecule interaction with Class B GPCRs in the future.

In the study, Liao and his colleagues were looking for ways to sensitize sugar-metabolizing insulin by stimulating production of GLP1. Synthetic versions of this peptide have proven effective but of short duration so it had been abandoned by drug researchers.........

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January 10, 2007, 8:47 PM CT

People With Mental Health Disabilities

Sixteen years after Congress enacted the Americans with Disabilities Act (ADA), people with psychiatric disabilities are faring worse in court cases against employers for discrimination than are people with physical disabilities, researchers have found in a national study.

"People with psychiatric disabilities were less likely to receive a monetary award or job-related benefit, more likely to feel as though they were not treated fairly during the legal proceedings and more likely to believe they received less respect in court," said Jeffrey Swanson, Ph.D., a study investigator and an associate professor of psychiatry at Duke University Medical Center.

"When people with disabilities sue their employers for discriminating against them, they are hoping to achieve a tangible result, such as getting their job back or receiving some monetary compensation," Swanson said. "But that's not the only thing that matters. They want to be heard and treated fairly. Sometimes that alone can signal victory for a plaintiff, but if that doesn't happen, it can add insult to injury".

The findings are published in the current issue (Volume 66, Issue 1) of the Maryland Law Review. The research was funded by the National Institute of Mental Health.

The researchers said the study is the first to examine how individuals with psychiatric disabilities fare in the court system.........

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January 7, 2007, 9:14 PM CT

New HIV test To predict drug resistance

Researchers at Duke University Medical Center have developed a highly sensitive test for identifying which drug-resistant strains of HIV are harbored in a patient's bloodstream.

The test may provide physicians with a tool to guide patient treatment by predicting if a patient is likely to become resistant to a particular HIV drug, said one of its developers, Feng Gao, M.D., associate professor of medicine. Drug resistance is one of the most common reasons why therapy for HIV, the virus that causes AIDS, fails.

The test, which detects genetic changes, or mutations, in HIV, also may help scientists understand how the constantly evolving virus develops drug resistance, Gao said. He said such knowledge ultimately may result in the development of new treatments designed to evade resistance.

The findings will appear online on Sunday, Jan. 7, 2007, in the journal Nature Methods, as well as in the journal's February 2007 print edition. The work was supported by the National Institutes of Health and the Duke Center for AIDS Research.

Duke has filed for a provisional patent on the technology, and the researchers are considering ways to establish a new company to pursue its development or to license the technology to an existing company, Gao said.

Because HIV genes mutate so easily and the virus reproduces so rapidly, most people who are infected have many different forms of the virus in their bodies. In some cases, mutated strains take on new properties that make them more resistant to the drugs used in antiretroviral therapy, the primary means of treatment for HIV infection.........

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December 26, 2006, 7:51 PM CT

Acid Suppression Medications And Hip Fracture

Use of the drugs proton pump inhibitors (PPIs) for the treatment of acid-related diseases such as gastro esophageal reflux disease (GERD) is associated with a greater risk of hip fracture, according to a study in the December 27 issue of JAMA.

Potent acid suppressive medications such as PPIs have revolutionized the management of acid-related diseases. Millions of individuals have been using these medications on a continuous or long-term basis, according to background information in the article. Some research has shown that PPI therapy may decrease insoluble calcium absorption or bone density in certain patients. These factors could increase the risk for hip fracture, which has a death rate during the first year after the fracture of 20 percent. Among those who survive this period, 1 in 5 require nursing home care and often an emergency department visit, hospitalization, surgery, and rehabilitation, with huge health care costs.

Yu-Xiao Yang, M.D., M.S.C.E., of the University of Pennsylvania School of Medicine, Philadelphia, conducted a study to determine what effects PPI therapy has on bone metabolism and hip fracture risk in a large group representative of the general population. The researchers analyzed data from the General Practice Research Database (1987-2003), which contains information on patients in the United Kingdom. The study group consisted of users of PPI therapy and nonusers of acid suppression drugs who were older than 50 years.........

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December 13, 2006, 8:07 PM CT

Elimination Of Menstrual Cycles Safe

Scientists for the first time have demonstrated the safety and effectiveness of continuous-use oral contraceptives that can eliminate menstrual cycles, as per a research studyreported in the recent issue of Contraception.

While low-dose oral contraceptives reducing the number of menstrual periods to four are on the market, this study marks the first time scientists have shown that it's safe to eliminate them, said lead investigator David F. Archer, M.D., professor of obstetrics and gynecology at Eastern Virginia Medical School.

"It is felt that the relief of menstrual cycle symptoms during continuous use of the contraceptive is a significant improvement in the quality of life," said Archer.

Traditional birth-control regimens include 21 days of active hormones with seven days of placebos to continue monthly menstruation. During menstruation, a number of women suffer a variety of symptoms including headaches, bloating and irritability, Archer said.

In the study, conducted at 92 sites in North America, scientists used a birth-control pill consisting of 20 micrograms of ethinyl estradiol and 90 micrograms of levonorgestrel, a formulation being developed by Wyeth Pharmaceuticals under the name Lybrel. Healthy, sexually active women between 18 and 49 years old were given a continuous regimen without any breaks or placebos.........

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December 6, 2006, 8:20 PM CT

Sticky Proteins And Drug Action

How drugs such as adrenalin do primarily one thing - in this case, increase the heart rate - now makes more sense to scientists.

"Any time you get a sudden jolt, adrenaline (a.k.a. epinephrine) is why your heart rate goes up," says Dr. Nevin A. Lambert, a biophysicist at the Medical College of Georgia. "If your heart is about to stop and the doctor administers epinephrine, that is what he or she is trying to do".

New research, would be published in the Nov. 21 print issue of Proceedings of the National Academy of Sciences and already available online in Early Edition, may help explain how cells respond correctly to epinephrine.

Most drugs never get inside cells; they interact with external receptors that activate G proteins roaming inside cells. "If you are going to change the way the cell works, you have to transduce a signal from outside a cell inside," says Dr. Lambert. "It's like a relay. G proteins interact with receptors; they run into them, they collide with them. The receptor itself does not do anything other than turn on these G proteins".

There are only four classes of G proteins, but cells contain thousands of copies of them which interact with hundreds of surface receptors. Each G protein is actually three protein subunits stuck together: alpha, beta and gamma.........

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